Air conditioner compressor



Oct. 22, 1968 E. J. OUNSTED 3,406,634

A IR CONDIT IONER COMPRES SOR Filed May 29. 1967 3 Sheets-Sheet l Oct.22, 1968 E. J. OUNSTED 3,406,634

AIR CONDITIONER COMPRESSOR Filed May 29, 1967 5 Sheets-Sheet 2\\\\\\\\\\\\\\\\\\\\\\\\k m y wN Z N\ \N N W 53% Q C w WWW MW m Oct. 22,1968 E. J. OUNSTED 3,406,634

AIR CONDITIONER COMPRESSOR Filed May 29, 1967 5 Sheets-Sheet 5 i f3 9,5% f7 1- f? i /7 f4 2 ZJzazkr Q7. BY

United States Patent 3,406,634 AIR CONDITIONER COMPRESSOR Edwin J.Ounsted, Ann Arbor, Mich., assignor to Ford Motor Company, Dearborn,Mich., a corporation of Delaware Filed May 29, 1967, Ser. No. 641,983Claims. (Cl. 103-121) ABSTRACT on THE DISCLOSURE vAn air conditioningcompressor assembly having a stationary vane carrying member or statorsurrounded by a floating cylinder. A rotor or housing mounted forrotation about the axis of the stator surrounds the floating cylinderand has internal eccentric hubs on which the floating cylinder isjournalled. As the housing is rotated, the floating cylinder isoscillated around the vane carrying stator. This oscillation causesinward and outward movement of the vanes and a pumping action betweenthe stator and the floating cylinder.

Summary of the invention Air conditioning compressors used in motorvehicle air conditioning systems are subject to a number of designlimitations which as yet have not been fully satisfied. There aredefinite size limitations that must be met since the modern enginecompartment with all the power accessories to be found therein, such aspower steering units, power brake units, smog control units, oversizebat: teries and the like, make it almost impossible to find room for theair conditioning system. The compressor must operate efliciently over awide range of speeds since in most cases the compressor is directlydriven from the engine and is directly responsive to the speed of theengine. The compressor must have low noise and vibrationcharacteristics. This latter feature has become increasingly importantsince much time and money is being spent on reducing all external engineand body noises that'could be transmitted to the passenger compartment.

It has been found that a vane type pump or compressor has distinctadvantages over a piston type compressor particularly from thestandpoint of noise, vibration and harshness. A conventional type vanecompressor in which the vanes are carried by a rotor rotating within astationary housing has the undesirable feature, however, that the vanesare subject to high frictional wear as they are dragged around the wallsof the pump chamber.

The present invention has as its objective the provision of a vane typepump or compressor in which the frictional engagement of the vanes withthe inner surfaces of the compression chamber is a negligible factor inthe life of the pump or compressor. I

The air conditioner compressor assembly embodying the present inventioncomprises a stationary cylindrical vane carrying member having aplurality of circumferentially spaced vanes mounted therein and havingseparate fluid inlet and outlet ports circumferentially spaced betweensaid vanes in communication with inlet and outlet conduits,respectively. A vane retainer cylinder encompasses said vane carryingmember. This vane retainer cylinder has a cylindrical body portion of aninternal diameter greater than the external diameter of the vanecarrying member to thereby provide a plurality of compression chambersseparated by the vanes of the vane carrying member. The stationarycylindrical vane carrying member and the vane retainer cylinder arehoused within a rotary housing mounted for rotation about the axis ofthe vane carrying member. This rotary housing encompasses the vaneretainer cylinder in spaced radial relation- Ice ship to the cylindricalbody portion of the latter and has internal eccentric hubs on which thevane retainer cylinder is journalled.

Rotation of the rotary housing, by means'of a belt drive, with the beltbeing received on a pulley portion of the housing, causes the vaneretainer cylinder to oscillate on the eccentric hubs around the vanecarrying member. The oscillatory motion of the v-ane retainer cylindercauses inward and outward movement of the vanes in a fluid compressionaction in the several compression chambers between the stationary vanecarrying member and the vane retainer cylinder.

Description of the drawing Further objects, advantages and features ofthe present invention will become more apparent as the descriptionproceeds, reference being had to the accompanying drawings, wherein:

FIG. 1 is an end elevational view of the compressor embodying thepresent invention;

FIG. 2 is a view taken on the line 22 of FIG. 1;

FIG. 3 is a view on the line 3-3 of FIG. 2;

FIG. 4 is an enlarged view on the line 4-4 of FIG. 3;

FIG. 5 is a view on the line 5-5 of FIG. 3; and

FIG. 6 is a view on the line 66 of FIG. 3.

Description of the preferred embodiment Referring now to the drawings,the compressor assembly generally designated 11, is illustrated as beingmounted on a simple support stand 12 having a base 13 and upstandinglegs 14 and 15. It will be understood, however, that the support stand12 would have a more sophisticated design to fit the packagingconditions of the vehicle engine with which it would be associated aspart of a vehicle air conditioning system.

Fixedly mounted on the support stand 12 is a stationary cylindrical vanecarrying member or stator, generally designated 16. The vane carryingmember 16 has a cylindrical body portion 17 and two hollow cylindricalor tubular appendages 18 and 19 projecting axially from respective sidesof the cylindrical body portion 17.-The tubular appendages 18 and 19extend to the support stand legs 14 and 15, respectively, where they areclamped by capplates 21, see FIG. 1.

As best seen in FIGS. 3 and 4, the vane carrying member 16 is radiallyslotted to receive a plurality of radially extending vanes 22. Asillustrated, there are four of these vanes 22. These vanes are paired sothat each vane has another vane diametrically opposite-to it. As shownin FIG. 4, each pair of vanes are in alignment with a pair of rods 23which extend through suitable apertures 24 in the cylindrical bodyportion 17. Between the ends of the rods 23 and the vanes 22 arecompression springs 25 contained in spring pockets 26. The purpose ofthis construction and arrangement will be hereinafter explained.

The cylindrical body portion 17 of vane carrying member 16 and the vanes22 mounted therein are encompassed by a vane retainer cylinder,generally designated 27. The vane retainer cylinder 27 has an annular orring-like body portion 28 of an internal diameter somewhat greater thanthe external diameter of the cylindrical body portion 17 of the vanecarrying member 16 (see FIG. 3). The annular body portion 28 is closedat both ends by end plates 29 which have central hub portions 31. Theend plates 29 are bolted, as by bolts 32, to the end faces of theannular body portion 28. The vane retainer cylinder is supported onneedle bearings 33 mounted within the hub portions 31, as will be morefully explained.

The vane retainer cylinder 27 and the vane carrying member 16 containedtherein are both encompassed by a rotary housing, generally .designated34. The rotary housing 34 is fabricated of a number of parts whichinclude a tubular body portion 35 having its inner bore 36 eccentricallyoffset from its outer cylindrical surface 37 (see FIG. 3). At its rightend as viewed in FIG. 2, the tubular body portion 35 has an integralreduced diameter portion 38 having in its surface a V-belt receivinggroove 39.'The groove 39 is adapted to receive a V-belt 41 coupled to asuitable driving pulley (not shown) on a prime mover such as anautomobile engine.

The right end of the tubular body portion 35, as viewed in FIG. 2, isclosed by an end face plate 42 having an inwardly extending cylindricalportion 43 terminating in a stepped portion 44 which forms an eccentrichub 45 against which the needle bearings 33 revolve.

The hub 45 is bored concentrically with the tubular appendage 19 of thevane carrying member 16 and is rotatably journalled for rotation on thelatter by a needle bearing assembly 46.

The left end of the tubular body portion 35 has a cylindrical extension46 bolted thereon to balance the integral cylindrical extension 38 atthe right side of the body portion 35. The cylindrical extension 47 isclosed by an end face plate 48 which is symmetrical to the end faceplate 42. The end face plate 48 has an inwardly extending cylindricalportion 43 terminating in the accentric hub 45 against which the leftend needle bearings 33 revolve. A needle bearing assembly 46 rotatablyjournals the left end of rotary housing 34 on the tubular extension 18of the vane carrying member 16.

In FIG. 2 the conduit 49 of the tubular appendage 19 is labelled SUCTIONand the conduit 51 of the tubular appendage 18 is labelled DISCHARGE.The fiow of fluid, such as Freon, through the compressor from thesuction side to the discharge side is controlled by four pairs of reedvalves, there being one pair of such reed valves between each pair ofvanes 22, or in effect, one pair of valves for each of the fourcompression chambers defined by the four vanes.

Between each pair of vanes 22, the vane carrying member 16 has anaxially extending slot 52 which has bolted therein a suction reed valveassembly 53. The reed valve assembly comprises a reed valve retainerplate 54 which is attached by bolts to the vane carrying member. Boltedat one end by a bolt 56 to the outer surface of the retainer plate 54 isa resilient reed 57. The free end of the reed overlies an aperture 58 inthe retainer plate 54 which is in communication with the passageway 59through the cylindrical body portion 17. The passageway 59 communicateswith the suction inlet 49.

It will be noted that the suction reed valves 53 open into thecompressor chambers formed by each pair of vanes 22 and the opposingcircumferential surfaces 61 and 62 of the cylindrical body portion 17and the annular body portion 28 of the vane carrying member 16 and thevane retainer cylinder 27.

Between each pair of vanes 22, the vane carrying member 16 has a secondaxially extending slot 63 which is counterbored to provide a recess 64.The slot 63 has bolted therein by bolts 65 a discharge reed valveassembly 66. The discharge reed valve assembly comprises a reed valveretainer plate 67 to which is bolted by bolt 68 a resilient reed valve69. The free end of valve 69 is positioned to cover aperture 71 in theretainer plate 67. This aperture 71 is in communication with thecompression chamber between the related vane 22.

It will be noted in FIG. 2 that the reed valve 69 defleets downwardlyinto recess 64 to permit communication between aperture 71 andpassageway 72 in the vane carrying member 16 leading to dischargeconduit 51.

The vane carrying member 16 and the vane retainer cylinder 27 are sealedagainst any leakage of refrigerant, such as Freon, by a plurality ofstrategically located carbon seals, O-rings and the like. Examples arethe carbon seals 73 and the O-rings 74 located around the tubularappendages 18 and 19 outboard of the eccentric hubs 45. Two otherimportant carbon seals are the seals 75 surrounding the cylindricalportion 43 of the housing end face plates 42.

No attempt is made to seal the rotary housing 34. On the contrary, thehousing 34 has a plurality of air inlet apertures 76 in its cylindricalextension 74. The tubular body portion 35 of the housing 34 has aplurality of angularly inclined slots 77 providing air outlets for theair taken in through the inlet 76. This fiow of air is intended to coolthe working parts of the compressor as they become heated through thecompression action on the refrigerant.

Operation The operation of the compressor is relatively simple. It isdriven by a conventional V-belt 41 which rotates the outer housing 34about the axis of the vane carrying member 16. Because of theeccentricity of the hubs 45 on which the vane retainer cylinder 27 issupported by the needle bearings 33, the vane retainer cylinder 27iscaused to oscillate about the axis of the vane carrying member 16.Because of this oscillation, the chambers between the vanes 22 areconstantly going through a series of volumetric expansions andcontractions. This is best seen with reference to FIG. 3. In FIG. 3, thechamber between the uppermost two of the vanes 22 is at its minimumvolume whereas the chamber between the two lowermost vanes 22 is at itsmaximum volume.

The refrigerant to be compressed enters through the suction conduit 49which is in communication through four suction passageways 59 with eachof the suction reed valve assemblies 53. In those chambers which areundergoing volumetric expansion, the suction reed valves 57 will beopened into the chambers permitting the flow of refrigeranttherethrough. Once the vane retainer cylinder 27 has oscillated to aposition in which a chamber begins to compress the refrigerant therein,the respective suction valve will automatically be closed and thedischarge reed valve assembly 66 will open, that is, the reeds 69 willpermit communication between the aperture 71 and the passageway 72leading to the discharge conduit 51.

Under ideal conditions the only forces directly being exerted on thevanes would be the forces pushing them radially inwardly and outwardly.It will be understood, however, there is some friction in the system andthat the vane retainer cylinder will have a tendency to slip relative tothe ends of the vanes 22 causing some frictional wear on the vane ends.It will be readily apparent that the frictional engagement between theends of the vanes and the inner circumference of the vane retainerassembly is a minimal factor compared to the friction that would beencountered if the vane retainer assembly is held stationary and thevane carrying member 17 is rotated as in many conventional rotary typecompressors.

It will be understood that this invention is not to be limited to theexact construction shown and described but that various changes andmodifications may be made without departing from the spirit and scope ofthe invention as defined in the appended claims.

I claim:

1. An air conditioner compressor assembly, comprising:

a stationary cylindrical vane carrying member having .a plurality ofcircumferentially spaced vanes mounted therein and having separate fluidinlet and outlet ports circumferentially spaced between said vanes incommunication with inlet and outlet conduits, respectively,

a vane retainer cylinder encompassing said vane carrying member,

said vane retainer cylinder having a cylindrical body portion of aninternal diameter greater than the external diameter of said vanecarrying member to provide a plurality of compression chambers separatedby the vanes of the vane carrying member,

and a rotary housing mounted for rotation about the axis of the vanecarrying member,

said rotary housing encompassing said vane retainer cylinder in spacedradial relationship to said cylindrical body portion and having internaleccentric hubs on which the vane retainer cylinder is journalled,

rotation of said rotary housing causing said vane retainer cylinder tooscillate on said eccentric hubs about the vane carrying member to causeinward and outward movement of thevanes and a fluid compression actionin the several compression chambers between the stationary vane carryingmember and the vane retainer cylinder.

2. An air conditioner compressor assembly according to claim 1, inwhich:

diametrically opposite vanes are synchronized for movement by rod andspring members extending between said vanes through the body of saidstationary vane carrying member so that as one vane reaches its minimumprojection outwardly of the surface of the vane carrying member thediametrically opposite vane will be urged to its maximum projectionoutwardly.

3. An air conditioner compressor according to claim 1,

in which:

the rotary housing has a series of cooling air inlets at one end thereofand a plurality of cooling air outlets in the peripheral wall thereof.

4. An air conditioner compressor according to claim 1, in which:

the rotary housing has pulley means at one end thereof adapted toreceive a drive belt.

5. An air conditioner compressor according to claim 1,

in which:

the flow of fluid through said inlet and outlet ports is controlled byreed valves peripherally mounted on said stationary cylindrical vanecarrying member.

6. An air conditioner compressor according to claim 5, in which:

there is an intake reed valve and a discharge reed valve between eachadjacent pair of vanes.

7 An air conditioner compressor assembly comprising:

a stationary cylindrical member having a plurality of substantiallyradially movable vanes projecting outwardly from the cylindrical surfacethereof,

a vane retainer cylinder encompassing said vane carrying member andhaving its inner circumferential surface in abutting contact with theends of said radially movable vanes,

the center of said vane retainer cylinder being offset from the centerof said stationary cylindrical member,

each pair of adjacent means, the surface of the stationary cylindricalmember therebetween and the surface of the vane retainer cylinderbetween the ends of said means defining a compression chamber, eachcompression chamber having inlet and outlet reed valves controlling thefluid flow into and out of said compression chambers from and to suctionand discharge conduits, respectively, and rotary means supporting saidvane retainer cylinder, said rotary means being rotatable about the axisof said stationary cylindrical member and having eccentric hub meansjournalled in end wall portions of said vane retainer cylinder, rotationof said eccentric hub means in response to rotation of the rotary meanscausing said vane retainer cylinder to progressively oscillate aroundsaid stationary cylindrical member, the oscillation of said vaneretainer cylinder causing said vanes to sequentially move outwardly andinwardly and said compression chambers sequentially to enlarge anddecrease in volume whereby fluid taken in through said intake reedvalves is compressed and discharged through said discharge reed valves.8. An air conditioner compressor assembly according to claim 7, inwhich:

diametrically opposite vanes are synchronized for movement by rod andspring members extending between said vanes through the body of saidstationary vane carrying member so that as one vane reaches its minimumprojection outwardly of the surface of the vane carrying member thediametrically opposite vane will be urged to its maximum projectionoutwardly. 9. An air conditioner compressor according to claim 7, inwhich:

the rotary means supporting the vane retainer assembly comprises arotary housing, said housing having a series of cooling air inlets atone end thereof and a plurality of cooling air outlets in the peripheralwall thereof. 10. An air conditioner compressor according to claim 9, inwhich:

the rotary housing has pulley means at one end thereof adapted toreceive a drive belt.

References Cited UNITED STATES PATENTS 399,822 3/1889 Blades 230153 X1,941,651 1/1934 Behlmer 103-121 X 2,030,952 2/1936 Wishart 103-121JAMES W. WESTHAVER, Primary Examiner.

